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Frontiers in Physiology 202216S rRNA gene sequencing for characterization of microbiomes has become more common in poultry research and can be used to both answer specific research questions and...
16S rRNA gene-based assessment of common broiler chicken sampling methods: Evaluating intra-flock sample size, cecal pair similarity, and cloacal swab similarity to other alimentary tract locations.
16S rRNA gene sequencing for characterization of microbiomes has become more common in poultry research and can be used to both answer specific research questions and help inform experimental design choices. The objective of this study was to use 16S rRNA gene sequencing to examine common sampling practices in broiler chicken studies such as: the required number of birds selected from a flock to adequately capture microbiome diversity, the differences between cecal pairs within the same bird, and whether cloacal swabs are representative of other alimentary tract (AT) locations. To do this, nine market age broilers were euthanized and immediately sampled in ten AT locations: crop, gizzard, proventriculus, duodenum, jejunum, ileum, cecal samples from each pouch, colon, and cloacal swab. DNA was extracted and subjected to 16S rRNA gene amplification and sequencing. Each location within the broiler AT hosts distinct microbial communities. When each sampling location was considered, it was found that sampling after 2.8 birds (range 2-4) resulted in less than 10% new amplicon sequencing variants (ASV) being added while sampling after 7.6 birds (range 6-10) increases new observed ASVs by less than 1%. Additionally, when cecal pairs from the same bird were evaluated, it was found that cecal pair mates are an adequate replication if interested in the total cecal microbiome but may be less useful if a rare lineage is of interest. Furthermore, when compared to other AT locations, the cecal microbiome was enriched in Firmicutes and Bacteroides while several lineages, most notably Lactobacillus, were under-represented. Finally, when cloacal swabs were compared to other AT locations, community similarity exhibited a direct distance relationship, i.e., the more aborad samples were the more similar they were to the swab. These findings indicate that while cloacal swabs can approximate overall changes in microbiome composition, they are not adequate for inferring changes to specific taxa in other parts of the AT tract-even those that are highly abundant within the microbial community. These data provide new insights guiding appropriate sample size selection within flocks and add to the consensus data regarding cecal pair similarity and destructive versus non-destructive sampling methods.
PubMed: 36338471
DOI: 10.3389/fphys.2022.996654 -
Journal of Hazardous Materials Jan 2023Plastic pollution in the world's oceans is ubiquitous and increasing. The environment is inundated with microplastics (< 1 mm), and the health effects of these less...
Plastic pollution in the world's oceans is ubiquitous and increasing. The environment is inundated with microplastics (< 1 mm), and the health effects of these less conspicuous pollutants is poorly known. In addition, there is now evidence that macroplastics can release microplastics in the form of shedding or digestive fragmentation, meaning there is potential for macroplastic exposure to induce direct and indirect pathology through microplastics. Therefore, there is an urgent need for data from wild populations on the relationship between macro- and microplastic exposure and the potential compounding pathological effects of these forms of plastics. We investigated the presence and impact of microplastics in multiple tissues from Flesh-footed Shearwaters Ardenna carneipes, a species that ingests considerable quantities of plastics, and used histopathological techniques to measure physiological responses and inflammation from the plastics. All organs examined (kidney, spleen, proventriculus) had embedded microplastic particles and this correlated with macroplastic exposure. Considerable tissue damage was recorded, including a significant reduction in tubular glands and rugae in the proventriculus, and evidence of inflammation, fibrosis, and loss of organ structures in the kidney and spleen. This indicates macroplastics can induce damage directly at the site of exposure, while microplastics can be mobilised throughout the body causing widespread pathology. Collectively, these results indicate the scope and severity of the health impacts of plastic pollution may be grossly underestimated.
Topics: Animals; Plastics; Microplastics; Environmental Monitoring; Waste Products; Water Pollutants, Chemical; Birds; Inflammation
PubMed: 36303350
DOI: 10.1016/j.jhazmat.2022.130117 -
Viruses Oct 2022Proventricular dilatation disease (PDD) caused by parrot bornavirus (PaBV) infection is an often-fatal disease known to infect Psittaciformes. The impact of age at the...
Proventricular dilatation disease (PDD) caused by parrot bornavirus (PaBV) infection is an often-fatal disease known to infect Psittaciformes. The impact of age at the time of PaBV infection on organ lesions and tissue distribution of virus antigen and RNA remains largely unclear. For this purpose, tissue sections of 11 cockatiels intravenously infected with PaBV-4 as adults or juveniles, respectively, were examined via histology, immunohistochemistry applying a phosphoprotein (P) antibody directed against the bornaviral phosphoprotein and in situ hybridisation to detect viral RNA in tissues. In both groups of adult- and juvenile-infected cockatiels, widespread tissue distribution of bornaviral antigen and RNA as well as histologic inflammatory lesions were demonstrated. The latter appeared more severe in the central nervous system in adults and in the proventriculus of juveniles, respectively. During the study, central nervous symptoms and signs of gastrointestinal affection were only demonstrated in adult birds. Our findings indicate a great role of the age at the time of infection in the development of histopathological lesions and clinical signs, and thus provide a better understanding of the pathogenesis, possible virus transmission routes, and the development of carrier birds posing a risk to psittacine collections.
Topics: Animals; Bornaviridae; Cockatoos; Parrots; Mononegavirales Infections; RNA, Viral; Tissue Distribution; Bird Diseases; Phosphoproteins
PubMed: 36298736
DOI: 10.3390/v14102181 -
Metabolites Oct 2022A total of 896 1-day-old straight-run (Ross-308) broilers were used to investigate the interactive effects of protein source (PS), diet structure (DS) and butyric acid...
A total of 896 1-day-old straight-run (Ross-308) broilers were used to investigate the interactive effects of protein source (PS), diet structure (DS) and butyric acid (BA) on live performance and carcass characteristics, gut development and its morphology and apparent ileal digestibility (AID) of protein and amino acids (AA). Eight experimental diets comprising 8 replicates with 14 birds each were tested in a 2 × 2 × 2 factorial arrangement with complete randomized design by two levels of BA (0 and 0.1%), two forms of DS (whole vs. ground wheat) and two PS, i.e., soybean meal and canola meal (SBM vs. CM). Throughout the entire experimental period (0 to 35 d), broilers fed SBM-based diets exhibited better (p < 0.05) growth performance (feed intake (FI), body weight gain (BWG) and feed conversion ratio (FCR)), carcass parameters (p < 0.05), gut health (p < 0.05), and nutrient digestibility (p < 0.05) than CM-fed broilers. Dietary whole wheat (WW) positively affected FI (p = 0.001), BWG (p = 0.004) and FCR (p = 0.035) during the overall experimental period. Broilers fed WW had 6, 5, 8, 11 and 10% lower empty relative weights of crop, proventriculus, jejunum, ileum and colon and 25 and 15% heavier gizzard and pancreas, respectively, with longer villus height (p < 0.001), reduced crypt depth (p = 0.031) and longer villus height-to-crypt depth ratio (p < 0.001) than those fed ground-wheat-based diets. Broilers fed WW had greater (p < 0.05) AID of CP and most of the AA. Butyric acid supplementation resulted in improved (p < 0.05) growth performance and digestibility of threonine, valine, leucine, isoleucine, phenylalanine, serine and aspartate. The broilers consuming SBM had 28% lower abdominal fat than those fed CM-based diets. In conclusion, harmful consequences of a less digestible PS can partially be compensated by the inclusion of WW, and supplementation of BA further reduces these detrimental effects.
PubMed: 36295891
DOI: 10.3390/metabo12100989 -
Animals : An Open Access Journal From... Oct 2022Gum Arabic (GA) belongs to the Fabaceae family and contains indigestible soluble fibers (80-85%) that could be fermented by commensal bacteria to enhance performance,...
Gum Arabic (GA) belongs to the Fabaceae family and contains indigestible soluble fibers (80-85%) that could be fermented by commensal bacteria to enhance performance, immune response, and intestinal integrity. This study aimed to investigate the effects of GA on performance, serum biochemical indicators, microbiota, immune-related gene expression, and histological changes in chickens. Six GA levels (0.0, 0.12, 0.25, 0.5, 0.75, 1.0%) were allocated using a total of 432 1-day-old male chickens (12 replicates with 6 chickens each). Growth performance was evaluated on days 10 and 24 of age. Blood parameters, organ pH levels, and intestinal health were determined on day 10 of age. Results showed that GA at 0.12% increased weight gain and 0.12 to 1.0% decreased feed intake but was best in feed conversion ratio and production efficiency except for 1.0% on day 1-10 of age. There was an increase in the thymus weight at GA level 0.25 to 0.75%. GA decreased the pH value of the proventriculus (at 0.50 and 1.0%) as well as the duodenum and cecum (at 0.12 and 1.0%). Chickens fed GA between 0.25 to 1.0% had higher protein and HDL, but lower cholesterol, LDL, and creatinine. Globulin was increased at 0.50% GA, while glucose and triglycerides were decreased (at 0.25 and 0.75% GA, respectively). The immune-related gene expression was reduced, except for 0.25% GA, which increased IL-10. Furthermore, chickens fed GA (0.25 to 0.75%) had higher spp. and lower spp. and . When chickens received GA, the villus length and length to crypt ratio were higher, which also improved the integrity of intestinal epithelial cells and early duodenal development. We conclude that using GA (0.25 to 0.75%) as a natural prebiotic positively affects the performance, microbiota, immune response, morphology, and gut health of post-hatched chickens. More studies are needed to determine the potential mechanism of GA on broiler chickens.
PubMed: 36290194
DOI: 10.3390/ani12202809 -
Animals : An Open Access Journal From... Oct 2022Newcastle disease is a devastating poultry disease that often causes significant economic losses in poultry in the developing countries of Africa, Asia, as well as South...
Newcastle disease is a devastating poultry disease that often causes significant economic losses in poultry in the developing countries of Africa, Asia, as well as South and Central America. Velogenic Newcastle disease virus (NDV) outbreaks are associated with high mortalities, which can threaten household livelihoods, especially in the rural areas, and lead to loss of high-quality proteins in the form of meat and eggs, as well as household purchasing power. In this study, we exposed unvaccinated Ghanaian and Tanzanian chickens of six local ecotypes to velogenic NDV strains, measured NDV response traits, sequenced their DNA on a genotyping-by-sequencing platform, and performed variance component analyses. The collected phenotypes included: growth rates (pre- and post-exposure); lesion scores (gross lesion severity) in the trachea, proventriculus, intestine, and cecal tonsils; natural antibody levels; anti-NDV antibody levels at 7 days post exposure (dpe); tear and cloacal viral load at 2, 4, and 6 dpe; and survival time. Heritability estimates were low to moderate, ranging from 0.11 for average lesion scores to 0.36 for pre-exposure growth rate. Heritability estimates for survival time were 0.23 and 0.27 for the Tanzanian and Ghanaian ecotypes, respectively. Similar heritability estimates were observed when data were analyzed either separately or combined for the two countries. Survival time was genetically negatively correlated with lesion scores and with viral load. Results suggested that response to mesogenic or velogenic NDV of these local chicken ecotypes could be improved by selective breeding. Chickens that are more resilient to velogenic NDV can improve household livelihoods in developing countries.
PubMed: 36290141
DOI: 10.3390/ani12202755 -
Veterinary Sciences Oct 2022The purpose of this work was to study the effects of substitution of fishmeal by housefly larvae at different rates and different physical states in the diet of local...
The purpose of this work was to study the effects of substitution of fishmeal by housefly larvae at different rates and different physical states in the diet of local chickens. Five diets consisted of LFD, 25DL, 50DL, 25FL and 50FL, respectively, larval-free, 25%-dried-larvae, 50%-dried-larvae, 25%-fresh-larvae and 50%-fresh-larvae diet, in which 0, 25 and 50% of fishmeal was replaced by dried and fresh larvae, was formulated. A total of 165 local chickens of three weeks old, divided into 15 boxes in batches of 11 animals were raised. The experiment consists of three replications of five treatments. At 14 weeks of age, sixty chickens were slaughtered. Butchery skills and sensory characteristics were evaluated. Thus, a small variation of the ultimate pH from 5.63 to 5.55 between the different types of meat, and a carcass yield around 66%, was recorded. Any effects of substitution rate and physical state of housefly larvae on growth performance was not observed. Feet and proventriculus percentages increased in chickens fed 25% substitution. Liver and spleen percentage, and redder breast meat, increased in chicken fed dried larvae. Yellowness of the breast, thigh-and-drumstick meat and juiciness increased with 50% substitution. There is need of an investigation for liver and spleen enlargement and housefly larvae containing pigments. Thus, housefly larvae up to 50% substitution can be a suitable alternative to fishmeal in local chicken diets.
PubMed: 36288166
DOI: 10.3390/vetsci9100553 -
Journal of Animal Science Jan 2023In this study, the efficacy of different nonstarch polysaccharide (NSP) enzyme sources on wheat ingredients and wheat basal diets in vitro were evaluated by simulating...
In this study, the efficacy of different nonstarch polysaccharide (NSP) enzyme sources on wheat ingredients and wheat basal diets in vitro were evaluated by simulating the avian digestive tract. In Exp. 1, pH level was increased from 2.0 to 8.0 by simulating the avian digestive tract. The relative enzyme activities of xylanase A, B, and C and β-glucanase X at pH 3.0-3.5 were higher (P < 0.05) than those at pH 2.0 or 7.0-8.0. The optimal pH levels of 3.5 and 7.0 were screened by simulating the proventriculus and small intestine, respectively to evaluate the efficacy of NSP enzyme on wheat sources. In Exp. 2, wheat 1 contained the highest content of NSP fractions and the lowest digestibility in vitro dry matter (IVDMD) and energy (IVED) in wheat samples. Therefore, wheat 1 was selected for hydrolysis research under different NSP enzyme sources and levels (1,500, 4,500, 13,500, 40,500, 121,500 U xylanase/kg and 250, 500, 1,000, 2,000, 4,000 U β-glucanase/kg) in vitro. The hydrolysis of wheat on the basis of the released reducing sugar content was determined by xylanase sources A > B > C (P < 0.05) and β-glucanase sources of X > Y (P < 0.05). On the basis of the hydrolysis, the optimum dose of xylanase A and β-glucanase X were 40,500 U/kg and 2,000 U/kg, respectively. Subsequently, the completely randomized designs involving 2 NSP enzymes treatments × 2 endogenous digestive enzymes treatments (Exp. 3), as well as 2 wheat basal diets × 2 NSP enzymes treatments (Exp. 4) were used to evaluate the efficacy of NSP enzymes on dietary nutrient digestibility. The addition of NSP enzymes (40,500 U xylanase A/kg and 2,000 U β-glucanase X/kg) increased the IVDMD and IVED of wheat 1 without endogenous enzymes (P < 0.05), while the IVDMD and IVED of wheat 1 with endogenous enzyme were only slightly increased (P > 0.05). The addition of NSP enzymes could increase the IVDMD and IVED of corn-wheat-soybean meal diet (P < 0.05), but had no effect on those of wheat-cottonseed meal rapeseed meal diet (P > 0.05). In conclusion, xylanase and β-glucanase additions could effectively eliminate the adverse effects on wheat and wheat basal diets at the optimal pH levels of 3.5 and 7.0 by simulating the proventriculus and small intestine parts, respectively. The efficacy of NSP enzymes was influenced by the enzyme sources, dietary type, and the interaction of endogenous enzymes.
Topics: Animals; Animal Feed; Animal Nutritional Physiological Phenomena; Diet; Dietary Supplements; Digestion; Endo-1,4-beta Xylanases; Gastrointestinal Tract; Polysaccharides; Triticum
PubMed: 36259767
DOI: 10.1093/jas/skac334 -
Poultry Science Dec 2022Improving feed efficiency is one of the main goals of chicken breeding and production. The function of the digestive system, where feed is digested and nutrients are...
Improving feed efficiency is one of the main goals of chicken breeding and production. The function of the digestive system, where feed is digested and nutrients are absorbed, is closely related to feed efficiency. However, the association between feed efficiency and the development of different digestive organs in chickens remains unclear. Here, we investigated the individual feed efficiency of 207 broilers during the fast-growing period with an electronic feeder and examined the characteristics of 8 organs of their digestive system (the liver, bile, proventriculus, gizzard, duodenum, jejunum, ileum, and cecum) at market age. Both the feed conversion ratio (FCR) and residual feed intake (RFI) were significantly negatively correlated with the gizzard weight (GW) and significantly positively correlated with the relative weight of the liver (RLW). Additionally, we found an obvious negative relationship between the FCR and cecal length (CL). A two-tailed t test further confirmed these correlation analysis results. Specifically, compared to birds with the lowest feed efficiencies, the GW of broilers with the highest feed efficiencies (the lowest FCR or RFI) was 22.74% and 17.97% higher, respectively. The RLW of chickens with the highest feed efficiencies was 10.82 to 13.73% less than that of chickens with the lowest feed efficiencies. In addition, we found that increased CL (5.42-12.09%) was significantly associated with better feed efficiency. Thus, our study showed that the feed efficiency of broilers was related to the development of the gizzard, liver, and cecum. These findings provide new insight into the genetic and physiological regulation of feed efficiency in broilers.
Topics: Animals; Chickens; Animal Feed; Gizzard, Avian; Proventriculus; Digestive System; Diet
PubMed: 36252505
DOI: 10.1016/j.psj.2022.102184 -
Animals : An Open Access Journal From... Oct 2022This study aimed to determine the effect of the addition of oat hull (0−3%) and high amounts of cereal grains to the diet of broiler chickens in terms of the...
This study aimed to determine the effect of the addition of oat hull (0−3%) and high amounts of cereal grains to the diet of broiler chickens in terms of the development of the upper gastrointestinal tract, individual microbial counts in the crop and ileum, and the effect of dietary fibre fractions on microbial changes from the beak to the ileum. In the 28 d trial, 162 one-day-old Hubbard Flex male chickens with an average body weight of 44.5 g were randomly allocated to 27 metabolic cages. The experiment consisted of a randomised, one factorial ANCOVA design composed of a covariate with two ANOVA factorial designs containing nine treatments (3 × 3): three sources of cereal grains (maize, wheat, and barley, with a minimum amount of 500 g · kg−1, each with nine replications) and three levels of oat hull (0, 1, and 3%, each with nine replications). At the end of the study, 81 chickens (9 in each treatment) were slaughtered to determine the weight of the individual organs and characterise the intestinal microbiota. The application of 3% oat hull to the cereal diets increased the weight of the proventriculus and the gizzard (6.3 and 27.3 g, respectively) in comparison to diets without the addition of this structural component (6.0 and 23.7 g). Higher crop counts of total aerobic microbes (6.29 log CFU · g−1) and Lactobacillus spp. (4.05 log CFU · g−1) were observed in diets containing wheat grain compared with maize (4.62 and 3.55 log CFU · g−1, respectively). The main reason for the microorganism’s growth (p < 0.05) was the amount of soluble dietary fibre and hemicelluloses present in the diet: total aerobic microbial count (respectively r = 0.918 and r = 0.816) and Lactobacillus spp. (respectively r = 0.416 and r = 0.442). Barley diets decreased (p < 0.05) E. coli counts in the ileum (2.69 log CFU · g−1) vs. maize and wheat diets (3.41 and 3.45 log CFU · g−1, respectively), mainly due to the increase in the amount of insoluble dietary fibre in the diet (r = −0.462). Reduced total yeast and mould counts in the ileum were also observed (p < 0.05) in connection with the presence of soluble dietary fibre and hemicelluloses in diets (r = −0.397 and −0.398, respectively).
PubMed: 36230460
DOI: 10.3390/ani12192721